In early March, as Russia deployed thousands of troops in Crimea to back the process of the peninsula's annexation, it also began to build up its troop presence on the country's border with Ukraine.

At the same time, Russia denied that the buildup was anything more than a military exercise.

Many suspected that Moscow's next target would be Ukraine's south and east -- where there are large Russian-speaking populations -- and reacted skeptically to Russian Foreign Minister Sergei Lavrov's repeated denials that Moscow had "plans to send troops into the rest of Ukraine.

But since the apparent failure of a de-escalation agreement signed in Geneva last week, Lavrov's rhetoric has become harsher -- and in an interview with RT on April 23 -- he all but said Russia was on the brink of war with Ukraine.

See how his statements have evolved over the past five weeks below:

March 14: After a meeting with U.S. Secretary of State John Kerry, Lavrov said "Russia does not have -- and cannot have -- any plans to invade the southeastern regions of Ukraine."

March 29: On Russian state TV: "We have absolutely no intention and no interests in crossing the Ukrainian border -- absolutely [none]."

April 11: Responding to a question on Russian state TV about whether Moscow had plans to take over the south and east of Ukraine: "We can't have that wish -- it goes against Russia's fundamental interests."

April 23: On RT, Russia's state-run English-language news outlet: ""If we are attacked, we would certainly respond. If our interests, our legitimate interests, the interests of Russians have been attacked directly, like they were in South Ossetiafor example, I do not see any other way but to respond in accordance with international law. Russian citizens being attacked is an attack against the Russian Federation." Russia invaded Georgia in August 2008 after fighting broke out between Georgia and its Russia-backed breakaway territory of South Ossetia.